This invention relates generally to inflatable passive restraint systems for use in vehicles for restraining the movement of a seated occupant such as in the event of a collision and, more particularly, to an improvement in the structure for housing and positioning a gas generator and an inflatable bag in the vehicle.
Safety restraint systems which self-actuate from an undeployed to a deployed state without the need for intervention by the operator, i.e., "passive restraint systems," and particularly those restraint systems incorporating inflatable bags or cushions, as well as the use of such systems in motor vehicles have been the subjects of much discussion as the desirability of the use of such passive restraint systems has gained general acceptance.
Generally, it is common to utilize airbag module assemblies which include at least three basic components: 1) a cushion or airbag that is inflated with gas such as when the vehicle encounters a sudden deceleration, 2) an inflator which upon actuation serves to provide the gas used to inflate the airbag cushion, and 3) a reaction canister which typically functions as a structural housing supporting both the inflator and the airbag cushion while providing a mounting base for installation of the assembly in a vehicle and direction to the inflation gases resulting from the inflator.
Such reaction canister housing structures are typically in the form of an open-mouthed container, formed with a body portion, such as composed by one or more body parts, and with an end plate fastened at each opposed end of the container. Usually, the airbag cushion, in an uninflated and folded condition, is placed into and housed within such an open-mouth reaction canister housing.
It is known to construct reaction canister assemblies, using one or more part or parts formed by extrusion fabrication. In practice, the component parts of such prior art inflatable restraining devices, particularly the component parts of the reaction canister, e.g., the reaction canister body and the corresponding end plates, are commnonly joined and held together through the use of a multiple number of selected fasteners such as screws, rivets or bolts. For example, a selected fastener is typically passed through fastener holes which have been preformed in the respective parts to be fastened together. Such fastener holes commonly take the form of screw channels formed, during extrusion processing or otherwise, in or along the reaction canister body. Further, it is relatively common for reaction canister assemblies to rely on the inclusion and use of multiple fasteners in order for the reaction canister assembly to maintain needed or desired structural stability upon deployment of the associated airbag cushion, particularly at the chute or mouth portion of the reaction canister assembly wherethrough, upon proper actuation, the airbag cushion is deployed.
The manufacture and production of assemblies that utilize multiple fasteners typically require additional machinery and associated personnel. For example, facilities for the production of such assemblies which require multiple fasteners commonly include multiple fixture devices to effect proper fastener hole alignment for insertion of a fastener as well as a selected form or forms of driver devices in order to drive each fastener into the corresponding fastener hole. Such additional production steps slow the assembly process and increase the costs associated with such assemblies.
Furthermore, each fastener is an entity in and of itself with each such fastener needing to be secured and tightened to a specific torque, thereby complicating the assembly process. For example, in order to better ensure safety in and proper functioning of airbag module assemblies, the component parts of the assembly and typically including each fastener, as well as the particulars of each such component, is desirably recorded and tracked. Such recording and tracking operations, however, can become undesirably complicated and burdensome as the number of component parts for particular assembly designs is increased. In view thereof, airbag module assemblies are generally preferably designed to minimize the number of component parts used therein.
Thus, a relatively simple, low cost reaction canister assembly which: 1) reduces and/or minimizes the number of component parts incorporated therein and 2) reduces and/or minimizes the use of fasteners such as rivets, bolts, and screws to effect attachment and the problems associated with the use of such fasteners, such as those identified herein, is desired.